The detection of cells belonging to a GSM (Global System for Mobile Communications) cellular network may follow a four steps approach. First the mobile station may perform signal strength measurements (for example RSSI (Received Signal Strength Indication) or RXLEV (Reception Level)) on defined frequency carriers. Second it may start searching the Frequency Correction Burst (FCB) on the carriers with the highest signal strength. Third, after an FCB has been found, the mobile station may be able to calculate the position of the Synchronization Burst (SB) and receive it. Fourth, the SB may include the cell identifier and the training sequence code needed to receive the System Information blocks containing the cell configuration.
Based on the cell configuration, the Mobile Station may detect if the cell belongs to the correct GSM network and get the parameters to calculate the C2 value according to 3GPP TS 45.008 sec. 6.4 needed to consider about re-selection to the new cell based on the actual signal strength of the cell.
The Mobile Station may re-select to a new cell if its C2 values is higher than the C2value of the cell the Mobile Station is currently camping on for (for example) at minimum five seconds. Goal of this process is that the Mobile Station is camping on the cell with the highest C2 value belonging to the selected PLMN (Public Land Mobile Network) or an equivalent PLMN and fulfilling the condition for C2.
However, it may take time to find the FCB, receive the SB and the System Information blocks and this time may delay the re-selection of the Mobile Station to a new “best suitable cell” which may lead into a higher rate of cell re-selections or even into a higher rate of cell losses (for example out-of coverage events) and a lower mobile terminated call setup success rate in a fast moving environment. Thus, it may be desired to decrease the time needed to perform the re-selection.